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/* compile with:
*
* g++ -g -Wall tomemory.cpp `pkg-config vips-cpp --cflags --libs`
*/
#include <vips/vips8>
#include <iostream>
int
main(int argc, char* argv[])
{
if (VIPS_INIT(argv[0]))
vips_error_exit(nullptr);
for (int i = 0; i < 1000; i++) {
std::cout << "loop " << i << " ..." << std::endl;
// create a uint8 RGBA VImage
// `black` makes a mono image, so you need to explicitly tag it as srgb
const int width = 50;
const int height = 50;
const int channels = 3;
vips::VImage image =
vips::VImage::black(width, height, vips::VImage::option()
->set("bands", channels))
.copy(vips::VImage::option()
->set("interpretation", "srgb"))
.bandjoin(255);
// C libvips API to print a vips subclass ... handy for debugging
std::cout << "built: ";
vips_object_print_summary(VIPS_OBJECT(image.get_image()));
// render to an area of memory ... you can use `.data()`, but this is
// just as quick, and is threadsafe
size_t len;
void *data = image.write_to_memory(&len);
std::cout << len << " bytes of data at address " << data << std::endl;
// you own this pointer and must free it
g_free(data);
}
return 0;
}
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